Conventionally, a projector that makes an optical modulator to modulate a light beam irradiated by a light source in accordance with image information and form an optical image and projects the optical image in an enlarged manner has been known (for example, refer to Patent Publication 1 (JP2002-31843A)).
The projector includes optical components such as a lens for superposing the light beam irradiated by the light source on an image formation area of the optical modulator, a dichroic mirror for separating the light beam irradiated by the light source into three color lights (R, G and B) and a reflection mirror for conducting the light beam irradiated by the light source to the optical modulator, and an optical component casing, in which the optical components are housed and arranged at predetermined positions on an illumination optical axis of the light beam irradiated by the light source.
The optical component casing, which is a synthetic resin molding product manufactured by molding such as injection molding, has a groove formed on an inner side thereof to serve as an external position reference face of the optical component so that the optical component slides and fits to the groove.
However, the groove formed on the inner side of the optical component casing requires to be highly accurately formed to house and arrange the respective optical components at predetermined positions on the illumination optical axis of the light beam irradiated by the light source. Accordingly, since a molding die for the optical component casing needs to be a complicated profile and to be highly accurately manufactured, manufacturing of the optical component casing may be difficult while the production cost thereof may be increased.
An object of the present invention is to provide an optical component casing and a projector that can reduce the production cost and can easily be manufactured.